Are you a vegetarian or vegan endurance athlete? If you currently are or considering to change to a plant-based diet, it is important to understand how to ensure adequate nutrition intake. While a plant-based diet is known for its health benefits, nutritional deficiencies are common among vegetarians or vegans. Studies have shown that athletes who are vegetarian or vegan are at risk for low intakes of vitamin B12, vitamin D, riboflavin, iron, calcium, and zinc because of the restrictions that come with the diet.(1) These nutrients are mainly obtained from consuming animal-based foods. Consequently, protein intake may be low if such athletes do not carefully plan their diet.

Protein has many important roles, particularly as key to growth and repair mechanisms in our bodies. Athletes in particular need protein to repair exercise-induced damage to muscles and promote lean muscle tissue.(1) It supports immune system functions, which may be beneficial during training periods or competition. Common complaints of protein-deficient athletes include lingering colds, persistent injuries, poor recovery from workouts, hair falls, slow growing and fragile fingernails, and amenorrhea (for female athletes).(2) These symptoms associated with inadequate protein intake can hinder your athletic performance and hold you back from your training goals.

So, what do the experts recommend for vegetarian or vegan athletes?

In general, the American College of Sports Medicine, the Academy of Nutrition and Dietetics, and the Dietitians of Canada published a joint statement that recommended the protein requirements below:

Resistance/strength conditioning athletes: 1.6 to 1.7 g/kg body weight per dayNotice that the protein recommendation for vegetarian athletes is about 10% higher than endurance athletes.

Vegetarian athletes need slightly more protein because plant proteins are not digested as well as animal proteins.(1) To calculate your protein needs, simply multiply the recommended protein in grams by your body weight in kilograms. For example, if you weigh 70 kg, multiplying 1.3 g of protein (for vegetarian) by 70 kg will equal 91 g/kg of protein per day. Keep in mind the figures above are general recommendations. Your protein needs may be different from someone else’s because of factors such as the type of your training, intensity, duration, and gender.

Protein is made up of about 20 amino acids, of which 9 are considered essential (must be obtained from the diet). These 9 essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Vegetarian or vegan athletes commonly turn to supplemental dietary protein powders or isolates from whey, casein, egg, soy, pea, or hemp in order to make up protein needs. Although these supplements may claim as complete protein source, the bioavailability of amino acids may be affected by the different protein sources and purification methods.(3) You may have also heard of the use of branched chain amino acids (BCAA) to enhance endurance performance. This practice is not advocated by experts because of the lack of evidence for its safety and efficacy.(1) It is recommended that adequate protein intake is met through the diet without using amino acid supplements if your energy (calorie) intake is sufficient.

Vegetarian or vegan athletes would need to focus on adequate energy intake from nutrient-dense foods where 12 to 15% of energy is from protein. Lacto and lacto-ovo vegetarians can get protein from eggs and dairy. Total vegetarians or vegans would need to consume large amounts of plant proteins in order to meet needs. Some great sources of plant proteins are legumes, soy, grains, nuts/nut butters, and seeds/seed butters. Examples of these high quality protein sources are tofu, tempeh, lentils, edamame, split peas, oats, beans, whole wheat pasta, hemp seeds, sunflower seeds, pumpkin seeds, quinoa, sprouted grain breads, almonds, pine nuts, cashews, and wild rice. Vegetables such as broccoli, spinach, asparagus, bok choy, swiss chard, mushrooms, cauliflower, kale, spirulina, and watercress are also good sources of protein.(4)

It’s important to note that a source may be rich in one amino acid but deficient in another. So, plan your meals sensibly by using complementary sources of amino acids. An example of this would be combining rice and legumes in your meal. Rice is high in the amino acid methionine but low in lysine; while legumes are low in methionine, but high in lysine.(5) Consult a

qualified sports nutritionist such as a Registered Dietitian Nutritionist (RDN) to help carefully plan your diet and avoid any nutritional problems. You may go to http://www.eatright.org/find-an-expert to connect with an RDN who can properly guide the diet suitable for your sports nutrition needs.

By Zen Huynh, B.S. Nutrition Sciences

References:

1. American College of Sports Medicine, American Dietetic Association, & Dietitians of Canada. (December 2000). Joint

Position Statement: Nutrition and athletic performance. Medicine and Science in Sports and Exercise, 32(12), 2130-2145. 2. Clark, N. (1996). The Power of Protein. The Physician and Sports Medicine, 24:4, 11-12, DOI: 10.3810/psm.1996.04.1326